Privacy @lemmy.ml merlin @lemmy.dbzer0.com 3d ago

turning a raspberry pi 4B into a vpn router

Hi guys as title suggests I have a pi 4b 4gb and basically I want to connect it to my isp provided router (wired connection via a lan cable) and run an openvpn config on it and then connect it to an access point that i already have (this one is wired too via a usb to RJ45 adapter and lan cable). I know that I need to flash openwrt image on an sdcard and install it on pi4 but I don't know how to configure openwrt after that and honestly the guides on the forums and internet are a little confusing (I'm not that tech savy) also I read that not all usb to RJ45 adapters work with openwrt on pi4 but I don't know which one to buy. can anyone show me a fool proof guide or tell me what I need to do? Edit: thank you all amazing people for your input I found a Google wifi mesh solution second hand (ac-1304 model) that is supported by OpenWRT latest firmware for a good price and I went with that. Gonna find a proper use case for my Raspberry Pi in the future for now gonna keep it as a tinkering device.

45 comments

It sounds like a fun tinker project, but I don’t think the hardware will perform as well as you hope.
- Yeah like know open-vpn not gonna run well on it but wireguard is ok
You're not going to have fun when using OpenVPN. Even Wireguard will be a stretch. The Raspberry Pi does not have any hardware cryptography acceleration built-in and the raw compute power is very limited.

EDIT: Maybe you're going to have acceptable speeds after all? Take a look at the Raspberry results here: https://github.com/cyyself/wg-bench?tab=readme-ov-file#test-results
- Ran WireGuard on a Pi1 and it was fine for two users. Albeit WireGuard was the ONLY thing running aside from a Gitlab Runner.
  
  A 4b should be more than enough for many use cases except things that cause torrents of packets - but even then YMMV. It really depends on the workload.
  
  One bit of advice: if you can, use a storage device other than the micro-sd slot for the 4B. Again YMMV.
- You could use Tail Scale. It runs great on a Pi
  
  Define great. Tailscale doesn't even run Wireguard on the kernel level, but in user space.
  
  Can I run OpenVPN configs on it and use it as a roiter
- I already have a pi4B just wanted to find a use case for it. Is it really that bad? so how consumer routers with a fifth computing power run vpns?
  
  With hardware acceleration.
  
  Computing power isn't just a general quantity. Networking devices have dedicated chips in them to perform various parts of processes. (Encryption, decryption, encoding, decoding, compression, decompression, etc.)
  
  That's hardware acceleration. There are chips that are super efficient and powerful but they can only do that one thing.
  
  That's fine if you know exactly what the device is going to be for, so you can put in the exact chips it needs to do only what it needs to do.
  
  Sell it and get something more suited to the task instead of trying to shoehorn it onto a pi.
This may be helpful if you haven't found it yet. It has a full list of instructions to flash and configure openwrt on the rpi 4 with wireguard VPN. It says you can also do it with openvpn, but claim the speed was much slower.

https://www.instructables.com/Highspeed-VPN-Router-With-Raspberry-Pi/
- Thanks I haven't seen this guide before. It looks easy enough to follow
Maybe this one ? https://www.pivpn.io/
- Thanks but this is VPN server setup not a client
You have the pi, give it a go.

If it's inadequate then i'd recommend a used fanless thin-client type PC, such as a Wyse 5070, just make sure it comes with PSU and a few GB of RAM and SSD. And check reports of how much power it uses at idle.
- Thanks I will try running Wireguard on pi4. I never considered tin-clients before. What kind of OS these have? Can they run VPN clients?
  
  Usually they're normal x86 PCs with nothing unusual about them so just your Linux/BSD distro of choice. You can look up the processor model to see what crypto acceleration it can do, or see if there's any wireguard benchmarks available.
  
  Some have interesting processors like PowerPC, or other strange hardware, but avoid them unless interesting is what you're after.
Just install Raspbian and PiVPN and forward the right ports dude; Less complicated
- I miss not being a CGNAT user.
- Thanks but I think you misunderstood. I don't want to run a VPN server I want to run a openVPN client on a router
  
  Can you just get your own Router and use that instead of the ISP one? Then you can flash whatever firmware you want on it and you can run the openvpn/wireguard client at the router level. You won't need to combine the Pi with it.
- Yea seriously. So much easier lol.
I used RaspAP for the purpose lately, comes with VPN support built in
- Thanks This looks like exactly what I need. Installation seems easy enough. How do I configure it afterwards?

45 comments